1. Field of the Disclosed Embodiments
This disclosure relates to systems and methods for passively identifying positions of wireless devices, also referred to as geolocation.
2. Related Art
With the increasingly widespread proliferation of wireless devices accessing all manner of wireless networks, there has emerged a need for entities other than the particular user of a wireless device to accurately pinpoint a position of the wireless device. Accurate geolocation of a particular wireless device has, however, emerged as a problem for those involved in wireless research to overcome.
Research to date has produced partial solutions to the problem. For example, in order to obtain highly accurate geolocation results for wireless devices in open areas, highly-specialized equipment has been developed. This equipment is often cumbersome and expensive. The effectiveness of this equipment is, however, significantly adversely impacted when confronted with physical variables that emerge in other than open areas. These variables include signal reflection, variable power transmitters, and signal degradation due to walls and other objects shielding the signal from the wireless device.
Less sophisticated conventional solutions tend to be even less accurate. Accuracy can be increased using expensive antenna equipment, such as phased-array antennas, and detailed algorithms that make use of line-of-bearing concepts. But again, these solutions are cumbersome, and the expense associated with these solutions increases sharply as a desired level of accuracy increases.
Also, conventional geolocation systems often rely heavily upon connection to extensive external databases to facilitate looking up latitude and longitude coordinates for “known” locations in these databases. Such systems include SkyHook® or Wireless Geographic Logging Engine (WiGLE®). While systems such as these can provide accurate results, these systems require users manually adding information regarding access points to the huge databases. For example, WiGLE.net reports that the site has been “[m]aking maps since 2001,” with over 45 million located Wi-Fi networks as of October 2011. These databases are populated in advance, often by users “wardriving” neighborhoods. Wardriving is typically understood to refer to the act of searching for Wi-Fi wireless networks by users in moving vehicles, using portable computers or PDAs. These users then mass upload data on coarse locations of wireless access points to the databases. This process provides data that is often inaccurate and is, otherwise, unlikely to find certain access points such as a corporate access points, or newly-installed access points. Complex algorithms then comb the databases in an effort to resolve accuracy for the detected Wi-Fi access points.